Deep dyslexia and the right hemisphere hypothesis: Spoken and written language after extensive left hemisphere lesion in a 12-year-old boy

Abstract

The subject of this study was a right-handed Italian boy who sustained extensive left hemisphere damage after a massive subarachnoid haemorrhage at age 12 years; the right hemisphere was fully intact. Two years later, he had a residual anomic aphasia with good sentence construction and comprehension of speech. His reading aloud showed all the characteristics of deep dyslexia, although some minimal ability to read pseudowords remained. Writing and spelling were severely impaired, but without clear qualitative signs of deep dysgraphia. The overall pattern of performance is discussed with regard to the written language capacity of the nondominant right hemisphere and its contribution to normal reading. We conclude that in this case (and perhaps some other cases of acquired deep dyslexia), reading and writing may be mediated by a combination of left and right hemisphere sites.